Drone Footage of Arecibo Observatory Collapse
nsf.gov
nsf.gov
https://youtu.be/wGmDAjRRNXs?t=160
Surprisingly inaccurate and led me to think up until today that the reflector dish was a concrete bowl rather than a metal mesh.
My favourite accent tidbit is the English voice of the Shinkansen in Japan. It is voiced by an Australian, imitating a Canadian, who was imitating a British accent. The result is a totally ambiguous accent that sounds almost disconnected from geography. I say that as an Australian with a british twang.
That's like the modern version of the "mid-Atlantic" accent.
It's a Dutch person. They were always good at English and sounded like this.
Unfortunately for the viewing public it was facing the wrong way for the spectacle, but it'll probably be a fixture in engineering classrooms for years to come as a real world example of cable failure caught on video from up close.
Technically not impossible, the drone was close enough to the cable that it was likely exerting some force, no matter how small, on them. There is certainly some chance that in that moment that force was all that was needed to push it past the breaking point.
That said obviously from a practical standpoint if it were that close the the edge then the next gust of wind would have done it in anyways.
Cable number 2 goes in a more gradual way.
And on cable 3 there is a prominent wave before it falls to the ground.
Beyond the scientific value, it is (was) just a neat feat of engineering getting this built in the middle of the jungle.
SETI@home Arecibo Observatory documentary, 2012
https://www.youtube.com/watch?v=YX4PZ-fW2YA
An Insider's Tour of the Arecibo Observatory, July 2011
https://www.youtube.com/watch?v=kQJawfbjpxw
_Stare-Way to Heaven_, 73 Magazine article, August 1984 (page 34)
https://archive.org/details/73-magazine-1984-08/
Arecibo story from NASA Special Report 223 Cassette, June 1983 (Starts at 14:48)
https://archive.org/details/NASA223/NASA+223+cleaned-levelat...
2 days ago https://news.ycombinator.com/item?id=25264555
14 days ago https://news.ycombinator.com/item?id=25151342
23 days ago https://news.ycombinator.com/item?id=25045573
3 months ago https://news.ycombinator.com/item?id=24149346
Had I been in the area I'd have been tempted to set up my camera somewhere close (remember that the risk of collapse was known to be high).
https://www.nsf.gov/news/news_summ.jsp?cntn_id=301674&org=NS...
PS: Apparently I'm not alone with this idea, search engine comes up with hits. https://elistair.com/ even have a tether kit you can plug into some DJI models (and others) instead of the conventional battery pack. Out of Lyon, France, nice!
Arecibo was certainly still used actively, but it’s not the only observatory in its class - its not like the LHC or Hubble blowing up or something.
Is there any science you can do on extremely-large single-aperture telescopes that you can't do on comparable synthetic/multiple aperture telescopes?
There’s also https://en.wikipedia.org/wiki/RATAN-600, with a diameter of 575m, but that isn’t a fully filled dish.
Also sensitivity is given by total collecting area, which is very competitive for a single huge dish compared to a limited number of small dishes.
The receivers were also cooled with liquid helium IIRC so the noise floor was ridiculously low. Those features combined made for not just high resolution but high sensitivity observations. Most telescope arrays (to my understanding) have a higher noise floor.
The second feature was the ability to transmit. Arecibo has been used for decades as a radar to image asteroids and such. Many asteroids are too small and dark to effectively image with optical telescopes where Arecibo's radar is no problem. It also gets extremely accurate distance and rotation measurements.
The details get complex, but the gist of it is that arrays let you see bright small scale things, while single aperture telescopes let you see large scale that are dim.
Additionally, an array suffers with sensitivity and noise issues if they don't have enough antennas covering discrete distance pairings. This usually occurs at short baselines since array elements often have a minimum spacing. Single aperture telescopes have a large instantaneous gain factor due to their large collecting area, which is really hard to make up without an exceedingly large number of array elements. For example, Arecibo has the same collecting area as ~148 VLA dishes.
Data handling for an array is complex as well, as you need to mix and process the data from each telescope to sync them together (correlation), while a single aperture telescope doesn't need this step.
On the other hand, an array is generally much less sensitive to instrument noise as the cumulative signal means noise from a single array element has a much lower impact overall. Also, it generally dodges the single-point failure modes by being essentially redundant. You can still operate with one or more elements missing/out of action.
Each telescope type has it's pros and cons, and there are equally valid use cases for each one.
One thing that I imagine is quite difficult to perform on an array is the type of planetary radar Arecibo specialized in by nature of it's high-power S-Band radar (2.38GHz). With AO's S-Band radar, it was possible to get highly detailed imaging and orbital parameters of near-Earth Asteroids with short observations, while determining orbital parameters with optical observations can take numerous observations (and doesn't generally give you the same detailed 3d models). NASA's Goldstone Observatory is the next best telescope for this, but is nearly 20x less sensitive due to it's size and different operating frequency.
They've funded a good number of very expensive telescopes the last 20 years, the fact they didn't fund refurbishment here sees to tell a great deal about its actual value over building new radio telescopes.
MeerKAT: $330M
ELT: > $1B
GMT: $1B
Thirty Meter: $2.4B
Vera Rubin: $473M
James Webb: $10B++
WFirst: $4B
FAST (China): $180M
SKA: $1B
NOEMA: $70M
The last three are radio telescopes, which show both the range of funding available for new radio telescopes, and also serve as evidence we've gone beyond Arecibo.
I am no astro-rocket-surgeon, but I've been led to believe the problem with Arecibo is that it's giant dish was only an advantage for sending signals, while astronomy's overwhelming needs are to receive fainter signals which networks of dishes like SKA can do a much more amazing job at.
And while the planetary radar at Arecibo was one of a kind, and something that simply no other facility has right now, it is not the only food thing about AO. The huge collecting area and the low noise receivers were actually rather good at finding faint signals. Networks of dishes shine when it comes to resolving power, but they have their own drawbacks such as poor coverage of the u-v plane or the inability to image extended faint objects.
The capability to study near-Earth Asteroids and perform radar observations of the Moon and other large objects in our Solar System has definitely been diminished with this loss. Even Goldstone, the next most powerful radar telescope, is 20x less sensitive.
Not to mention the pairing of Arecibo's radars with the LIDAR system and it's HF Ionospheric heater system. I don't think saying Arecibo was not the only observatory in it's class is being rather disingenuous.
I've mentioned this in a previous comment [1] so I won't rehash it again, but here [2] is a statement from the NANOGrav collaboration - we have been using the Arecibo telescope on a weekly basis (along with the Green Bank telescope) to observe a large number of radio pulsars for over 15 years now, and when we announce the first detection of very low frequency gravitational waves, Arecibo data will play a critical role.
This loss really hurts. The US community is scrambling, and we are going to have to rely on the generosity of our international partners going forward - there's just not going to be enough telescope time to do all the science that we'd judged as very important through competitive review processes.
(And that's before we get into the unique radar capability, etc.)
[1] https://news.ycombinator.com/item?id=25154898 [2] http://nanograv.org/announcement,/press/2020/12/02/Arecibo.h...
They were worried about a 6 month delay, as it would seriously hurt their dataset. I assume they're devastated by the complete loss.
"Kevin Ortiz Ceballos, a physics student and aspiring astronomer at the University of Puerto Rico, said in an email that it had always been his dream to work at Arecibo.
Now he said, “It feels like the rug has been pulled out from under us and our dreams to work in astronomy in Puerto Rico has vanished.”"
[0] https://www.nytimes.com/2020/11/19/science/arecibo-observato...
e.g. Notionally 16km 'wide' https://en.wikipedia.org/wiki/Atacama_Large_Millimeter_Array
Or 6km https://en.wikipedia.org/wiki/Australian_Square_Kilometre_Ar...
and future the ~3000km (and total collection area of 1km^2) https://en.wikipedia.org/wiki/Square_Kilometre_Array
http://players.brightcove.net/679256133001/EkLWnGuil_default...
I was only trying to help.
This is so unbelievably sad to see. It reminds me of seeing Notre Dame burning last year.
Then again, it could have a snowball's chance in hell.
However, those all imply a > 0% chance which I honestly believe to be way too high.
The flyaway cost for domestic units of the F-35 are about $100M. [1]
The FAST radio telescope in China cost about $170M. [2]
While the Arecibo Telescope is significantly smaller, costs if rebuilt by US contractors would also be much higher than in China.
FAST can also only use about 300m of its 500m dish at a time due to limitations with focusing, so its effective size is closer to the Arecibo Telescope than its total size suggests.
So make that two F-35 and we're pretty much spot on and we'd have a budget for some 3-5 years of operation, too.
[1] https://f35.com/about/cost
[2] https://phys.org/news/2020-01-china-meter-fast-radio-telesco...
While I cannot find a number on the construction cost it seems that just running the observatory originally cost around ten million a year. So even if one F-35 was enough to finance a rebuild you would have to drop in a second to keep it running for just a few years.
You can buy arecibo for $120M. You can't do anything with it, and you give it on loan to the NSF. Then eventually you can transfer it to somebody else.
A full refit of Arecibo (obviously while it was still in one piece of course) would have likely been much cheaper than building an entirely new telescope.
So around 1000 times as heavy.
/s
“During ongoing aerial drone surveillance of the Arecibo Observatory’s 305-meter telescope, engineers observed additional breakages on the exterior wires of the remaining cables attached to Tower 4. This is the same tower to which the failed auxiliary cable and the broken main cable were attached.”
“Engineers have been examining the Arecibo Observatory 305-meter telescope since August, when one of its support cables detached.”
As I understand it from reading various news reports and a video from one Scott Manley, the damage from the recent earthquake had this collapse in the “when” column not “if”.
It seems fairly logical that it was being inspected precisely because this was anticipated. It's not like it was a surprise, it's exactly why they said they couldn't put manpower on it.
The first day we had a picture of the dish and some dust, the next day we had a video that was blinded by the sun, basically just audio. I didn't expect drones, but I'm grateful for that closure.
It seems to be snapping/frays at first, but then it seems like it was pulled out of its base
>seems like it was pulled out of its base
That's pretty much what happened. All of that weight on the cable pulled it away from its support structure on that tower. Gravity did the rest.
This thing was enormous.
And the risk would obviously have been gigantic as two cables had already snapped in the same place, so the remaining cables would be under insane and completely out of spec tensions, meaning they could fail at any point during the tentative transfer work.
[0] you either splay open the main cables and replace strands, or you need to jack the entire bridge from below to take down and replace the main cables at once
So to lower it, they'd have had to do a lot work adding stuff near the cables. Which they already knew to be a lot weaker than they were supposed to be, and of which two had already failed. That would have been the really negligent thing to do, instead of just removing all people from near the dish which was done.
There is no safety perspective if there is nobody there to get hurt. It has been evacuated for a long time now. Putting people anywhere near it would create the safety concern.
> The NSF made the announcement on November 19, 2020 that they would decommission Arecibo over the following few weeks after determining the safest route to do so with a safety exclusion zone immediately put in place.
The closest you can get to a safe lowering would be to sever all the anchor points simultaneously so that the platform falls vertically, rather than having a rotational component due to differing total tension forces. And even then, I don't see how that can be done particularly safely, given that any human in proximity to any of the towers at the time of premature collapse would be dead.
Just to reiterate: any person working on the support tower platform would have been dead. If not from the cable snapping (you can see how much damage it does to the remaining cables!), then from the support tower itself toppling over a few seconds later.
Steel beams will have a thickness of ~1cm steel at most, and steel plates will usually be much thinner.
Your idea of the world is pretty limited... Any beams above S8x23 / W12x53 (ie. the bottom of the beam tables) will have a web above 3/8".
The rectangular blocklike structure above the left side of the ring in this image is a roughly 8 ft x 8 ft x 20 ft (2.5m x 2.5m x 7m) shack. There might be a few humans in the frame though they're difficult to distinguish from equipment. The long structure descending off to the right is a gantry / catwalk.
https://upload.wikimedia.org/wikipedia/commons/1/13/Arecibo_...
To the right here:
https://www.ucf.edu/news/files/2018/02/ucf-arecibo-3.jpg
There are three people visible on the lower level here, directly below the stairs descending from the shack:
http://patriciadrichards.com/galleries/puertorico/arecibo-ob...
A construction photo. Behind the platform (upper left) is a bulldozer.
https://www.naic.edu/history_gal/jun151962.jpg
Full description:
The loss of Arecibo is painful and we have certainly lost capability but it isn't as bad as it looks.
https://news.ycombinator.com/item?id=25273623
https://dellweb.bfa.nsf.gov/NSFRqstAppropHist/NSFRequestsand...
We've fallen from the era where we sent echoes to our neighbours and the stars. When we found clearings in jungles and turned them into monuments to humanity. The time when we put our best foot forward and reached ahead, into the future, racing towards a brighter tomorrow for humanity.
I mourn for what has been lost.
The American century wasn't punctuated by a war, but by callous neo-mercantilism and disregard. The fall of America's aspirations from the heavens to the bottom of a sinkhole.
2020 is a year where SpaceX flew humans to space for the first time ever on a commercial vehicle, we created and started to distribute a vaccine for a never-before-seen virus in under a year, and we began to hook rural people who've never had access to high-quality internet up via a constellation of thousands of micro-satellites in LEO.
Sure, not everything is rosy, but we're still capable of some impressive feats of engineering.
Oh, and AlphaFold made an incredible leap in protein folding prediction. Like, a true "paradigm shift" in one of the most historically intractable problems in biology.
It’s kind of like the strategy in World War II: combine British ingenuity (DeepMind) with America. resources(Google).
$445 million in funding came as a grant from the German government, the rest from licensors. The German government has split another ~300 million or so on two other companies also working on vaccines. The US government did not contribute any funding to Pfizer's license.
I'd rather say it's a cool example of international collab and winning together than an American exceptionalism narrative ...
Just weeks after Apple unveiled the worlds fastest CPU core running on only 15 watts (with credit to a Brit architecture)?
If you look at the world through a filtered lens, of course you only see what you want to see.
Combined with the crucial failure of China that kept it under lid for too long, and followed by most of the rest of the world who also failed to contain it.
> used its power to steal medical equipment from other countries,
What are you talking about?
> developed a marvelous vaccine that will sell at a high price for other countries after vaccinating itself.
Good thing the world is capitalist by nature and we have two more (cheaper) vaccines ready to go, and Moderna will have to lower its price or sell it to those who are willing to pay them a premium for whatever reason. Right?
And I'm not sure if this is even a thing, but even if it is, what is your problem with each country requesting their labs to provide for their host nation's citizens first, specially in a case where all labs AFAIK received funding in some form by taxpayers?
SpaceX benefits NASA, but it is beholden to itself and it's shareholders, not the public (this being said as a massive SpaceX fanboy). Same with Apple. These companies exist to benefit themselves first, civilization second.
Conversely, if the development of the fastest CPU was funded by direct government funding it would be available as a foundation for future use by all, instead of other manufacturers needing to (re)discover the techniques themselves.
We went from having never left the ground under power to the moon in 65 years.
65. Years.
And in the subsequent 51?
We've gotten really good at making cheap electronics and our consolation prize is a low cost-to-orbit with no concrete plans to do anything extraordinary with it. Cool.
This feels truly like the end of an empire.
FASTs other difference is location: China. The community of people who would work at Arecibo is probably very different than the community that will work at FAST.
Fortunately, the message was sent to globular cluster M13, which is 22,000 light years away. As long as we get it done by the 47th millenium AD we should be fine.
Unfortunately, applying Parkinson's law to that task means we've got a lot of work to do!
[1] Side note: It somehow never ceases to amaze me how very year, my mental shortcut for approximating the number of years since a given date by subtracting it from 2000 gets less and less accurate.
Remember when partying like it was 1999 was something to achieve? The one that gets me every year is my graduation date from high school gets further away. It is now more easily measured in decades.
Unfortunately, the message was aimed at where M13 appears to us today. By the time the message gets there it will have moved. The message was, is, doomed to miss.
But I hope Ann Druyan's taking it okay.
But then again, with budget cuts and the decreasing budgets that science and climate organizations have been getting from the government lately, this is entirely possible.
https://news.ycombinator.com/item?id=25273623
https://dellweb.bfa.nsf.gov/NSFRqstAppropHist/NSFRequestsand...
Also try to tone down the hubris, Ozymandias.